…something that didn't look too much like an antenna…
The Raspberry Pi Zero W has a perfectly serviceable antenna which is simply a cavity formed between layers of copper and two tiny capacitors which look about like grains of salt.
Antenna design is not black magic. There are a few well-understood basic patterns and you parametrize those. Some of those look quite exciting and tuning the matching network is annoying if you've never done it before but typically you use a template for an antenna design and set the parameters to what gets you best simulation results, then prototype and measure and set the matching network to match your measurements. It's not magic, it's normal everyday engineering.
Coming up with new fundamental antenna designs feels a bit black magicky to us lowly electronics people, but that's just because it's more applied physics than engineering. Here's an example of how new antenna pattern design is done: http://sci-hub.tw/https://www.sciencedirect.com/science/arti...
Slightly related, an FPGA circuit designed by a genetic algorithm which ended working due to analogue effects and hardware-specific magnetic flux interference.
For this or other successful genetic algorithms, it would seem clear you still can’t know if it’s an optimal design simply because in most cases the number of designs tested would be a small fraction of the possible designs.
However, things like useful sound recognition being done with only a small number of logic gates (commenter below provided a nice article, thank you) make it hard to imagine doing much better.
I wonder if the process can be shown theoretically to offer any help in guaranteeing minimum bounds w.r.t. the optimal case, even if can’t be fully proven to be optimal.
The Raspberry Pi Zero W has a perfectly serviceable antenna which is simply a cavity formed between layers of copper and two tiny capacitors which look about like grains of salt.
You can read more at https://www.raspberrypi.org/magpi/pi-zero-w-wireless-antenna...
They are designed by some very clever Swedes. http://www.proant.se/en/news.htm
That second page shows the Raspberry Pi 3B+ whose antenna looks to be just a trace with the aforementioned grains of salt on it.